Naked Science Forum
Non Life Sciences => Geology, Palaeontology & Archaeology => Topic started by: katieHaylor on 30/10/2018 09:36:34
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Jacob asks:
Can wind weather limestone rock?
What do you think?
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Hi Jacob, welcome.
It is probably important to distinguish between weathering and erosion. Weathering is the process by which rocks are weakened and/or broken down, or dissolved. Erosion is the process by which material, once subjected to weathering, is removed.
In the case of aeolian (wind) effects the picture may be blurred by the fact that the wind itself is generally not what does the weathering, rather, it is material carried by the wind that weathers the rock. The wind may then do the transporting (erosion) of the weathered material.
Did you have a specific instance in mind?
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To supplement what Bill S said:
1. Wind with no particulates will not cause either weathering or erosion.
2. Wind with particulates, especially sand, but also silt, or smaller, will erode.
3. Water from moist wind may well condense on limestone which could lead to solution weathering.
4. Afterthought: partially loose limestone blocks attacked by a tornado or Category 5 hurricane could well be "eroded" from the bedrock.
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Interesting question.
In the US west, limestones commonly are the cap-rocks on ridges and mesas, mainly due to the dry conditions and relatively low permeability of limestone. Sandstones tend to weather more quickly due to wind and higher porosity.
Contrast this to the eastern US, where sandstone commonly forms the cap-rock; limestone tends to dissolve more quickly in the wetter climate leading to karst geography.
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Wind with no particulates will not cause either weathering or erosion.
Does blowing sand or dust count as erosion?
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Wind with no particulates will not cause either weathering or erosion.
Does blowing sand or dust count as erosion?
It counts as an agent of erosion. Erosion would be the consequence. However, wind borne sand is not the equivalent of wind.
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It counts as an agent of erosion. Erosion would be the consequence. However, wind borne sand is not the equivalent of wind.
I was thinking of things like sand dunes moving from one place to another. Would the removal of a dune from point "A" be classed as erosion?
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1. Wind with no particulates will not cause either weathering or erosion.
Are there any wind with no particulates, though?
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Without carrying abrasives, just fast moving air is not going to weather rock very quickly. But it will be a non-zero rate. What is wind but moving air molecules? And moving air molecules can certainly impart enough kinetic energy to break rocks up. I can imagine that a very powerful and focused stream of forced air could cause erosion on a timescale observable by impatient people.
(can we count sound and shockwaves as well?)
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Hi all,
there is a very pure creamy white limestone from Derbyshire that has been used on a lot of iconic buildings and monuments and many thousands of war graves headstones, which on its technical data sheet states between;
1-2 mm erosion per century
https://en.wikipedia.org/wiki/Hopton_Wood_stone